Blender Git Loki

2.5 - NLA SoC Branch Merged to 2.5!
(19863 to 21513)

Highlights of the new NLA System (and related Animation System changes):
* NLA Data is stored in AnimData alongside Action and Drivers. The NLA stack is evaluated before the Action, with the Action always overriding the results of the stack.
* NLA Data is arranged in 'Tracks', which act like PhotoShop layers. These can be muted, protected, and/or made to be played back by themselves
* Within each track, there can be multiple 'Strips'. There are 3 types of strip -> Action Clip (references some action), Transition (blends between the endpoints of two strips), and Meta (container for several strips that occur sequentially)
* FModifiers can be applied to strips, and strips can have animated influence/time controls. Playback for strips can also be backwards now!
* Playback can now go in forward and backwards directions.
* Animation Editors have been polished (unfinished features added, existing features cleaned up and made more consistent)

Notes for BuildSystem Maintainers:
* Only scons has been actively tested. Makefiles should work fine.
* MSVC ProjectFiles are broken due to the very way they work.
* CMake status unknown...

Other notes:
* Hopefully I haven't made any mistakes while doing the merge. More files than expected were showing some weird conflicts, so you may have some broken code...
* Not all old files (with NLA) data load exactly the same anymore. However, the bulk of the files out there should be ok (I hope)